X=Ray fluorescent screen contg. clear coloured plastics particles - which contain dyestuffs emitting red and shorter wavelength light and X=ray phosphor

摘要

Fluorescent screen for X-ray investigations contains coloured particles of transparent plastics (I) of a size suited to the size of the X-ray phosphor (IIe particles and in the 2-10, pref. 4-5 mu range. (I) contains 2 dissolved dyestuffs, one (III) emitting red in the fluorescent light of (II) and the other (IV) emitting a shorter wavelength. The amt. of (I) is 0.1-10, pref. 1 wt.% w.r.t. (II). The definition and light yield are both improved. (I) is pref. polyurea. (III) and (IV) may both be (soluble organic) fluorescent dyestuffs or (IV) a soluble organic fluorescent dyestuff and (III) a soluble metal complex dyestuff. In particular, (III) and (IV) are 2-anilido-4-(2',5,-dichlorobenzoylamino)-1,9-anthraquinone (IIIA) and diethyl 2,5-dihydroxyterephthalate (IVA) and are each mixed with (I) in an amt. of 1 wt.%, (IIIA) and (IVA) being partic. effective in conjunction with La2O3-LaBr:Tb as (II).